Reducing Width of forum

[DeadLOK]

how can i make my forum content more narrow like at bb.cs-skins.net (http://bb.cs-skins.net/)? Do i need a hack or is it a simple case of changing something in the control panel, although i cant see anything.

[Admin]

DeadLOK, please go to this (http://www.vbulletin.com/members/vbulletin.org.php) page and enter your username, to show you are licensed. (you will need to use your customer number and password to access that page)
Thank you.